CLEARWATER — On the day Craig Alan Wall Sr.'s infant son died, Clearwater police obtained a search warrant for a red Nikon digital camera that police say contained a video of the father saying he "was sorry he did something to the baby."

The warrant also says that two doctors examined the baby, who died at a hospital on Feb. 6, and found fractured ribs and swelling on the left side of the baby's brain.

And Wall Sr., 34, left a suicide note on a computer in the apartment where the baby was found injured.

Despite those factors, police have not charged Wall in connection with the infant's death. Eleven days after the baby, Craig Wall Jr., died, his mother, Laura Taft, was found fatally stabbed at her Clearwater apartment. Wall Sr. is in custody in Sumter County, where police say he fled after killing Taft, who was his girlfriend.

Police spokeswoman Beth Watts said the department is awaiting a final cause-of-death report from the Medical Examiner's Office.

"It's a death investigation," Watts said. "It hasn't been classified as a homicide. We can't say what caused that child's death."

In the warrant, the medical director for the Child Protection Team in Pinellas County, an arm of the state Department of Health, said she "suspected that the baby was either shaken or thrown onto a soft-type surface to cause injury to the brain."

Watts said that was considered speculative. "Every time we have a suspicious death, it's not always ruled a homicide. You have to look at other factors," she said.

Watts said the language in the search warrant about Wall's statement on the video clip was "very vague and does not constitute a confession."

Taft's other child, Connor Taft, is not related to Wall. He was with his father when Taft was stabbed to death early Wednesday morning.

Wall will be extradited to Pinellas County to face a murder charge, Watts said.

Times staff writer Dominick Tao contributed to this report. Rita Farlow can be reached at farlow@sptimes.com or (727) 445-4157.